﻿// Copyright (c) 2010-2014 SharpDX - Alexandre Mutel
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Runtime.Serialization;

namespace Molten.HalfPrecision;

/// <summary>
/// Defines a three component vector, using half precision floating point coordinates.
/// </summary>
[StructLayout(LayoutKind.Sequential)]
[Serializable]
public struct Half3 : IEquatable<Half3>
{
    /// <summary>
    /// Gets or sets the X component of the vector.
    /// </summary>
    /// <value>The X component of the vector.</value>
    [DataMember]
    public Half X;
    /// <summary>
    /// Gets or sets the Y component of the vector.
    /// </summary>
    /// <value>The Y component of the vector.</value>
    [DataMember]
    public Half Y;
    /// <summary>
    /// Gets or sets the Z component of the vector.
    /// </summary>
    /// <value>The Z component of the vector.</value>
    [DataMember]
    public Half Z;

    /// <summary>
    /// Initializes a new instance of the <see cref="Half3"/> structure.
    /// </summary>
    /// <param name="x">The X component.</param>
    /// <param name="y">The Y component.</param>
    /// <param name="z">The Z component.</param>
    public Half3(Half x, Half y, Half z)
    {
        this.X = x;
        this.Y = y;
        this.Z = z;
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="Half3"/> structure.
    /// </summary>
    /// <param name="x">The X component.</param>
    /// <param name="y">The Y component.</param>
    /// <param name="z">The Z component.</param>
    public Half3(float x, float y, float z)
    {
        this.X = (Half)x;
        this.Y = (Half)y;
        this.Z = (Half)z;
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="Half3"/> structure.
    /// </summary>
    /// <param name="x">The X component.</param>
    /// <param name="y">The Y component.</param>
    /// <param name="z">The Z component.</param>
    public Half3(ushort x, ushort y, ushort z)
    {
        this.X = (Half)x;
        this.Y = (Half)y;
        this.Z = (Half)z;
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="Half3"/> structure.
    /// </summary>
    /// <param name="value">The value to set for the X, Y, and Z components.</param>
    public Half3(Half value)
    {
        this.X = value;
        this.Y = value;
        this.Z = value;
    }

    /// <summary>
    /// Performs an implicit conversion from <see cref="Vector3F"/> to <see cref="Half3"/>.
    /// </summary>
    /// <param name="value">The value.</param>
    /// <returns>The result of the conversion.</returns>
    public static implicit operator Half3(Vector3F value)
    {
        return new Half3(value.X, value.Y, value.Z);
    }

    /// <summary>
    /// Performs an implicit conversion from <see cref="Half3"/> to <see cref="Vector3F"/>.
    /// </summary>
    /// <param name="value">The value.</param>
    /// <returns>The result of the conversion.</returns>
    public static implicit operator Vector3F(Half3 value)
    {
        return new Vector3F((float)value.X, (float)value.Y, (float)value.Z);
    }

    /// <summary>
    /// Performs an explicit conversion from <see cref="Vector2F"/> to <see cref="Half3"/>.
    /// </summary>
    /// <param name="value">The value.</param>
    /// <returns>The result of the conversion.</returns>
    public static explicit operator Half3(Vector2F value)
    {
        return new Half3(value.X, value.Y, 0.0f);
    }

    /// <summary>
    /// Performs an explicit conversion from <see cref="Half3"/> to <see cref="Vector2F"/>.
    /// </summary>
    /// <param name="value">The value.</param>
    /// <returns>The result of the conversion.</returns>
    public static explicit operator Vector2F(Half3 value)
    {
        return new Vector2F((float)value.X, (float)value.Y);
    }

    /// <summary>
    /// Tests for equality between two objects.
    /// </summary>
    /// <param name="left">The first value to compare.</param>
    /// <param name="right">The second value to compare.</param>
    /// <returns>
    /// <c>true</c> if <paramref name="left" /> has the same value as <paramref name="right" />; otherwise, <c>false</c>.</returns>
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static bool operator ==(Half3 left, Half3 right)
    {
        return Equals(ref left, ref right);
    }

    /// <summary>
    /// Tests for inequality between two objects.
    /// </summary>
    /// <param name="left">The first value to compare.</param>
    /// <param name="right">The second value to compare.</param>
    /// <returns>
    /// <c>true</c> if <paramref name="left" /> has a different value than <paramref name="right" />; otherwise, <c>false</c>.</returns>
    [return: MarshalAs(UnmanagedType.U1)]
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static bool operator !=(Half3 left, Half3 right)
    {
        return !Equals(ref left, ref right);
    }

    /// <summary>
    /// Returns the hash code for this instance.
    /// </summary>
    /// <returns>A 32-bit signed integer hash code.</returns>
    public override int GetHashCode()
    {
        unchecked
        {
            var hashCode = X.GetHashCode();
            hashCode = (hashCode * 397) ^ Y.GetHashCode();
            hashCode = (hashCode * 397) ^ Z.GetHashCode();
            return hashCode;
        }
    }

    /// <summary>
    /// Determines whether the specified object instances are considered equal. 
    /// </summary>
    /// <param name="value1" />
    /// <param name="value2" />
    /// <returns>
    /// <c>true</c> if <paramref name="value1" /> is the same instance as <paramref name="value2" /> or 
    /// if both are <c>null</c> references or if <c>value1.Equals(value2)</c> returns <c>true</c>; otherwise, <c>false</c>.</returns>
    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    public static bool Equals(ref Half3 value1, ref Half3 value2)
    {
        return (((value1.X == value2.X) && (value1.Y == value2.Y)) && (value1.Z == value2.Z));
    }

    /// <summary>
    /// Returns a value that indicates whether the current instance is equal to the specified object. 
    /// </summary>
    /// <param name="other">Object to make the comparison with.</param>
    /// <returns>
    /// <c>true</c> if the current instance is equal to the specified object; <c>false</c> otherwise.</returns>
    public bool Equals(Half3 other)
    {
        return (((this.X == other.X) && (this.Y == other.Y)) && (this.Z == other.Z));
    }

    /// <summary>
    /// Returns a value that indicates whether the current instance is equal to a specified object. 
    /// </summary>
    /// <param name="obj">Object to make the comparison with.</param>
    /// <returns>
    /// <c>true</c> if the current instance is equal to the specified object; <c>false</c> otherwise.</returns>
    public override bool Equals(object obj)
    {
        if (!(obj is Half3))
            return false;

        return this.Equals((Half3)obj);
    }
}
